I learned about Lord Rayleigh’s discovery of argon in my 2nd-year analytical chemistry class while reading “Quantitative Chemical Analysis” by Daniel Harris. (William Ramsay was also responsible for this discovery.) This is one of my favourite stories in chemistry; it illustrates how diligence in measurement can lead to an elegant and surprising discovery. I find no evidence that Rayleigh and Ramsay used statistics to confirm their findings; their paper was published 13 years before Gosset published about the t-test. Thus, I will use a 2-sample t-test in R to confirm their result.